1. Field of the Invention
The present invention relates to an electrical socket, and more particularly to an electrical socket having contact terminals floatably arranged within the socket thereby reducing deformation and strain resulted from interferential engagement between the contact terminals and the socket.
2. Background of the Invention
Electrical socket is widely used for electrically and mechanically connecting an electronic package such as a CPU to a PCB such as a motherboard. Generally, LGA (land grid array) socket serves as a role for electrically and mechanically connecting an electronic package and a PCB. A typical LGA socket is typically disclosed in U.S. Pat. No. 7,044,746 issued to Copper on May 16, 2006. The LGA socket generally comprises a number of spring contacts, which are configured with conductive pads on the electronic package. As the LGA socket and the electronic mate, the spring contacts exert a normal force on the conductive pads, thus ensuring proper electrical contact between the conductive pads of the electronic package and the spring contacts. Usually, a typical LGA socket further comprises a housing surrounding by a metallic frame, a loading device comprising a load plate and a load lever for pressing and securing a LGA package.
Generally, the spring contact has a retaining portion secured in passageway of the socket and a spring arm extending from the retaining portion and beyond an upper face of the socket, so as to mate with the corresponding conductive pad on the electronic package. Typically, during mating, the spring arms are deflected. Thus, the spring arm needs enough strength and flexibility to meet requirement of deformation. Since the higher the normal force provided by the spring arm, the more reliability can the socket connector provides. Accordingly, the industry tends to make the socket with higher normal force so as to provide a reliable interconnection.
Additionally, socket with higher normal force also brings some side effects. First, when an electrical socket having a plurality of high flexible contacts is mounted onto a PCB by a clamping fixture, the PCB will be more readily prone to warpage because the contacts exert a higher normal force than ordinary contacts. Additionally, a loading device is used in a LGA socket for pressing the electronic package toward the spring contact and securing the LGA package in the LGA socket. Thus, higher normal force will cause a higher interferential engagement force between the contact terminals and the socket when the LGA package is pressed and secured, especially when number of spring contacts exceeds more than 1500.
Therefore, there is a heretofore unaddressed need in the industry to address the aforementioned deficiencies and inadequacies.